running very rich after installling adjustable fuel pressure regulator

[bradcurtis15]

Since I installed my Adjustable Fuel Pressure Regulator I've been running a lot richer then normal. my wideband was reading about 11-12 range. I lowered the pressure down to 21lbs and it put my wideband at idle to the normal 14.8 range. Is it okay that i did this? I will be getting a new tune after I get my new turbo but I don't really want to spend the money on a tune that will only last a few more months.

 

[Bud92gsx]

You need to run the 700s at what pressure the manufacturer reccomends them to be.

Stock would be 38psi on a manual with 450s and 43.5psi with 390s on an auto.

 

[1000hpgsx]

Was it a used AFPR? Those can be rebuilt with new diaphragms.
Here is one for a specific aeromotive piece so you know what I mean

New Aeromotive Regulator Service Kit Part 13006 | eBay

 

[2slow4now]

I would say it very well may be the size of the AFPR fuel return orfice. Here is some reading I dug up on it although it is from AEM the function would still be about the same.

When should I change the AEM Fuel Pressure Regulator orifice?
A: AEM’s Adjustable Fuel Pressure Regulators feature patented interchangeable discharge ports. This allows the user to tailor the regulator return volume to match their fuel pump. A common problem that occurs when using a fixed port common on most “universal” regulators is that fuel pressure cannot be effectively controlled when the fuel pump volume is different than stock. In the case of too small of a discharge port, there is a large pressure spike associated with rapid deceleration because the orifice of the port cannot flow enough fuel when the diaphragm is fully deflected to the open position. This causes a momentary rich condition, which may lead to a rough idle quality until the pressure stabilizes. Conversely, if the discharge port orifice is too large the adjustment is difficult because the response of the fuel flow out of the orifice is too rapid, which makes the adjustment screw too sensitive. AEM Adjustable Fuel Pressure Regulators include three sizes of discharge port orifice, .100”, .150” and .200”. You can change the port by removing the diaphragm and unscrewing the installed port, and replacing it with a port with the desired size orifice. The size range provided with the kit is enough to cover any pump from a stock Honda pump to the largest pump available.